Mind Archive

Note for nested screen sessions, use "Ctrl+a a" to send commands to the inner screen,
and the standard "Ctrl+a" to send commands to the outer screen.

Key

Action

Notes

Ctrl+a c

new window

Ctrl+a n

next window

I bind F12 to this

Ctrl+a p

previous window

I bind F11 to this

Ctrl+a “

select window from list

I have window list in the status line

Ctrl+a Ctrl+a

previous window viewed

Ctrl+a S

split terminal horizontally into regions

Ctrl+a c to create new window there

Ctrl+a |

split terminal vertically into regions

Requires screen >= 4.1

Ctrl+a :resize

resize region

Ctrl+a :fit

fit screen size to new terminal size

Ctrl+a F is the same. Do after resizing xterm

Ctrl+a :remove

remove region

Ctrl+a X is the same

Ctrl+a tab

Move to next region

Ctrl+a d

detach screen from terminal

Start screen with -r option to reattach

Ctrl+a A

set window title

Ctrl+a x

lock session

Enter user password to unlock

Ctrl+a [

enter scrollback/copy mode

Enter to start and end copy region. Ctrl+a ] to leave this mode

Ctrl+a ]

paste buffer

Supports pasting between windows

Ctrl+a >

write paste buffer to file

useful for copying between screens

Ctrl+a <

read paste buffer from file

useful for pasting between screens

Ctrl+a ?

show key bindings/command names

Note unbound commands only in man page

Ctrl+a :

goto screen command prompt

up shows last command entered

The following scenarios were tested both on Fedora and Ubuntu, but should work on any linux distro at least.

If you want to try these examples out locally, just replace references to “@host” with “@localhost”.
You may also find my screen settings and screen keyboard shortcut reference useful.

Reattaching to a terminal

i.e. connecting again from another place or at another time.This is very useful as the managed programs keep running after you detach, even if they produce output, or you logout, or your dial-up hangs for e.g. Note Linux does not native support for reattaching processes to terminals (like VMS), so this is a very useful function indeed, and is a much better/easier solution than using disown or nohup. Of course screen must already be running before any of the managed programs.

To detach: Ctrlad
To reattach: screen -r

Multiple views of a terminal

Multiple users of a terminal

For security reasons, screen by default is installed so that other users within the system can not attach to your screen sessions. To allow this to be changed one must set screen to run SUID root by doing the following (once):

sudo chmod +s /usr/bin/screen
sudo chmod 755 /var/run/screen

Then user1 can share their session on host as follows:

screen -S shared-session

Ctrla:multiuser onCtrla:acladd user2

user2 on host can then connect to the shared session like:

ssh user2@host
screen -x user1/shared-session

Multiple read-only users of a terminal

For example one could give a group of users a demo by setting up read-only access to locked down account. This is an extension to just sharing a screen session, so again screen must run SUID root as described above. Then one could create a locked down “guest” account like:

Note user1 can see who has attached and the the size of their terminals with Ctrla: displays. This can be used to tell people to resize their terminals, or user1 can resize their own to the largest acceptable to everyone.

Note also that the settings above allow users to “wall” questions or comments to the group. If one wanted a richer interaction mechanism, then it would be advised that the group logs into a parallel realtime chat sytem, like IRC for example.